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Validation of the sperm quality analyzer and the hypo-osmotic swelling test for frozen-thawed ram and minke whale (Balaenoptera bonarensis) spermatozoa.

The object of the present study was to investigate the validation of the sperm quality analyzer (SQA) and the hypo-osmotic swelling (HOS) test with standard sperm analysis methods in frozen-thawed ram and minke whale spermatozoa. In rams, highly significant correlations were observed in the percentage of motile spermatozoa (P<0.01) and sperm concentration (P<0.01) between the standard and SQA methods. But, the percentage of morphologically normal spermatozoa did not significantly correlate between the standard and SQA methods. The percentages of swollen spermatozoa at 15 minutes by the HOS test were significantly correlated with the motility by the standard (P<0.05) and by the SQA (P<0.05) methods. For minke whale spermatozoa, the SVI (sperm viability index) values by the standard method were significantly (P<0.001) correlated with the sperm motility index (SMI) values by SQA. The percentage of motile spermatozoa was also significantly correlated (P<0.01) with the motility measured by SQA. Using different hypo-osmotic solutions and incubation times, the HOS test with 25, 100 and 150 mOsM did not show significant variations. Motility observed by the standard method and the percentage of swollen spermatozoa were significantly correlated (P<0.05). These results indicate that the SQA and HOS test can be utilized to assess the post-thawing motility of ram and minke whale spermatozoa, and that the SQA and HOS test values are significantly correlated in ram spermatozoa. However, sperm concentration and morphologically normal spermatozoa are not assessed accurately by SQA in minke whales.

Animals↗

Purification and properties of whale thyroid-stimulating hormone III. Properties of isolated multiple components.

Properties of the four purified components of whale thyroid-stimulating hormone (TSH) have been compared. The amino acid composition shows close similarity among these components. Their hexosamine and sialic acid contents are of the same magnitude, whereas the neutral sugar composition differs somewhat from each other. The molecular weight of whale TSH determined by sedimentation equilibrium is 29,000, and no difference in molecular weight as well as in Stokes radius as determined by gel filtration has been detected among these four components. The amino acid and carbohydrate compositions of whale TSH resemble those of TSH from other species, especially those of non-primate mammalian TSH. Whale TSH contains, unlike bovine TSH but like human TSH, 1-2 residues of sialic acid as a constituent carbohydrate.

Amino Acids↗

Serum chemistry and evidence of renal failure in the North Atlantic fin whale population.

Serum electrolytes, urea nitrogen, creatinine, albumin and globulin were studied in fin whales (Balaenoptera physalus) caught by commercial whalers in the North Atlantic (Denmark Strait area). Blood samples were obtained by catchment or cardiac puncture within 5-15 min of death and analyzed using automated spectrophotometric methods and flame photometry. Osmolality was determined for two serum samples by a vapor pressure method. Linear regressions determined for each measured serum variable vs. chase time suggested that pursuit of the whales prior to capture had no substantive effect on measured serum chemistry. As in other cetaceans, serum sodium, chloride, urea nitrogen and osmolality were distinctly higher in the fin whale than in terrestrial mammals. The total concentration of serum proteins, however, was 1.4-1.8 g/dl lower, on average, than reported in small toothed whales, and was similar to that of domesticated animals. One animal in this population showed alterations in serum chemistry which were consistent with renal failure.

Animals↗

[Primary structure of cyanogen bromide fragments of sei whale (Balaenoptera borealis) pituitary somatotropin].

5 fragments are isolated after the degradation of somatotropin from sei whale pituitary glands with cyanogen bromide: N-terminal 4-segmented; C-terminal 12-segmented with the internal disulfide bond; middle 25- and 30-segmented and a high molecular weight fragment following N-terminal tetrapeptide and bound with disulfide bond to 30-segmented fragment. Complete amino acid sequence of three shortest cyanogen bromide fragments is deciphered and N- and C-terminal sequence is investigated in two large fragments after their uncoupling under performic acid oxidation. Amino acid sequence is deciphered of a peptide obtained after trypsine hydrolysis of 30-segmented cyanogen bromide fragment. Comparison of amino acid sequence of whale somatotropin fragments with that of sheep, beef and human somatotropin has revealed that 57 out of 61 identified amino acid residues of whale somatotropin repeat amino acid residues in similar regions of beef somatotropin, 56--of sheep and only 42--of human somatotropins. Besdies, 4 of 5 revealed amino acid substitutions in whale hormone, as compared with sheep somatotropin, are amino acids which are present at the same positions in human hormone.

Amino Acid Sequence↗

Discerning between recurrent gene flow and recent divergence under a finite-site mutation model applied to North Atlantic and Mediterranean Sea fin whale (Balaenoptera physalus) populations.

Genetic divergence among conspecific subpopulations can be due to either low recurrent gene flow or recent divergence and no gene flow. Here we present a modification of an earlier method developed by Nielsen and Wakeley (2001), which accommodates a finite-site mutation model, to assess which of the two models of divergence is most likely given the observed data. We apply the method to nucleotide sequence data collected from the variable part of the mitochondrial control region in fin whales (Balaenoptera physalus) from the Atlantic coast off Spain and the Mediterranean Sea. Our estimations strongly favor a model of recurrent gene flow over a model of recent divergence and zero gene flow. We estimated the migration rate at two females per generation. While the estimated rate is high by evolutionary standards, exchange rates of this order of magnitude is low from an ecological and conservation perspective and entirely consistent with the current paucity of fin whale sightings in the Strait of Gibraltar today. Intensive commercial shore-based whaling during the 1920s removed substantial numbers of fin whales in the Strait of Gibraltar and this local population has seemingly since failed to recover.

Animals↗

Blood rheology of Weddell seals and bowhead whales.

Red blood cell (RBC) aggregation and blood viscosity are important determinants of in vivo blood flow dynamics and, in marine mammals, these parameters may impact diving physiology by altering blood oxygen delivery during the diving response. Weddell seals are superb divers and exhibit age-related patterns in blood oxygen chemistry and diving ability. By contrast, bowhead whales are not long duration divers, and little is known of their blood properties relative to diving. The present study was designed to compare rheological characteristics of blood from Weddell seal pups, Weddell seal adults, and from adult bowhead whales: blood viscosity and RBC aggregation in plasma and in polymer solutions (i.e., RBC "aggregability") were measured. Salient findings included: (1) significant 4- to 8-fold greater aggregation in blood from adult seals compared with pups and human subjects; (2) 2-to 8-fold greater aggregation in bowhead whale blood compared with human blood; (3) compared to human red cells, enhanced RBC aggregability of RBC from adult seals and whales as determined by their greater aggregation in polymer solutions; (4) increasing RBC aggregation and aggregability of seal pup blood over a seven day period following birth; (5) significantly greater blood viscosity for adult seals compared with pups at both native and standardized hematocrits. These results indicate that, for both species, hemorheological parameters differ markedly from those of humans, and suggest progressive changes with seal age; the physiological implications of these differences have yet to be fully defined.

Adult↗

A 1H NMR comparison of the met-cyano complexes of elephant and sperm whale myoglobin. Assignment of labile proton resonances in the heme cavity and determination of the distal glutamine orientation from relaxation data.

The met-cyano complex of elephant myoglobin has been investigated by high field 1H NMR spectroscopy, with special emphasis on the use of exchangeable proton resonances in the heme cavity to obtain structural information on the distal glutamine. Analysis of the distance dependence of relaxation rates and the exchange behavior of the four hyperfine shifted labile proton resonances has led to the assignment of the proximal His-F8 ring and peptide NHs and the His-FG3 ring NH and the distal Gln-E7 amide NH. The similar hyperfine shift patterns for both the apparent heme resonances as well as the labile proton peaks of conserved resonances in elephant and sperm whale met-cyano myoglobins support very similar electronic/molecular structures for their heme cavities. The essentially identical dipolar shifts and dipolar relaxation times for the distal Gln-E7 side chain NH and the distal His-E7 ring NH in sperm whale myoglobin indicate that those labile protons occupy the same geometrical position relative to the iron and heme plane. This geometry is consistent with the distal residue hydrogen bonding to the coordinated ligand. The similar rates and identical mechanisms of exchange with bulk water of the labile protons for the three conserved residues in the elephant and sperm whale heme cavity indicate that the dynamic stability of the proximal side of the heme pocket is unaltered upon the substitution (His----Gln). The much slower exchange rate (by greater than 10(4] of the distal NH in elephant relative to sperm whale myoglobin supports the assignment of the resonance to the intrinsically less labile amide side chain.

Animals↗

A Norwegian penthrite grenade for minke whales: hunting trials with prototypes and results from the hunt in 1984, 1985 and 1986.

A penthrite grenade to replace cold harpoons in the Norwegian minke whale hunt was developed in 1983-1985. Data on survival times for 259 minke whales were collected from the trials in the 1984-86 hunting seasons, when 3 different prototypes were used. About 45% of the whales were killed instantaneously. The median survival time was 72 s. A substantially higher percentage of instantaneous deaths was recorded for penthrite grenades than for cold harpoons. The criteria for death were cessation of flipper movement, relaxation of the mandible, or sinking without any active movement. Some animals dived before the criteria could be controlled. If the central nervous system, heart, lungs or main vessels were damaged, a high percentage of the animals died instantaneously. In most cases, hits and detonations outside the thorax and central nervous system resulted in longer survival times than hits in the thorax. Survival time increased with whale size and range for animals not killed instantaneously. Marksmanship, technical and functional reliability of equipment and hunting techniques were all crucial to a good result. Better training of gunners, improved weapons and hunting equipment and more rapid reshooting of wounded animals would reduce the proportion of long survival times.

Animals↗

Neuroanatomy of the killer whale (Orcinus orca) from magnetic resonance images.

This article presents the first series of MRI-based anatomically labeled sectioned images of the brain of the killer whale (Orcinus orca). Magnetic resonance images of the brain of an adult killer whale were acquired in the coronal and axial planes. The gross morphology of the killer whale brain is comparable in some respects to that of other odontocete brains, including the unusual spatial arrangement of midbrain structures. There are also intriguing differences. Cerebral hemispheres appear extremely convoluted and, in contrast to smaller cetacean species, the killer whale brain possesses an exceptional degree of cortical elaboration in the insular cortex, temporal operculum, and the cortical limbic lobe. The functional and evolutionary implications of these features are discussed.

Animals↗

On the communicative significance of whistles in wild killer whales (Orcinus orca).

Killer whales (Orcinus orca) use pulsed calls and whistles in underwater communication. Unlike pulsed calls, whistles have received little study and thus their function is poorly known. In this study, whistle activities of groups of individually known killer whales were compared quantitatively across behavioural categories. Acoustic recordings and simultaneous behavioural observations were made of northern resident killer whales off Vancouver Island in 1996 and 1997. Whistles were produced at greater rates than discrete calls during close-range behavioural activities than during long-range activities. They were the predominant sound-type recorded during socializing. The number of whistles per animal per minute was significantly higher during close-range behavioural activities than during long-range activities. Evidently, whistles play an important role in the close-range acoustic communication in northern resident killer whales.

Animals↗

Genetic characteristics of western North Pacific sei whales, Balaenoptera borealis, as revealed by microsatellites.

Genetic characteristics of sei whales, Balaenoptera borealis, inhabiting the western North Pacific were analyzed at 17 microsatellite loci in a total of 89 whales obtained from the area between 37 degrees N-45 degrees N and 147 degrees E-166 degrees E in 2002 (N=39) and 2003 (N=50). All the loci analyzed were polymorphic over the samples, some of the loci had more than 10 alleles, indicating a high level of genetic variation within samples. No significant deviation from the expected Hardy-Weinberg genotypic proportion was observed at the 17 loci in the samples. No evidence of genetic heterogeneity in allele frequencies was observed between sexes within samples as well as between the two temporally different samples, indicating a single population of sei whales inhabiting the western North Pacific. We finally tested and demonstrated that the population appeared not to suffer from genetic bottleneck as a result of population decline from past commercial whaling.

Alleles↗

Aggregation of killer whale platelets.

The aggregation of blood platelets is a crucial step in normal hemostasis for all mammals. Circulating platelets are sensitive to a large variety of physiologic and non-physiologic stimulants, some of which are formed or exposed in conjunction with vascular damage or endothelial cell denudation. In addition, drastic pressure changes activate human platelets. Killer whale platelet function, on the other hand, is very intriguing since these animals do not seem to experience untoward platelet reactions during or after diving to great depths, nor do they experience abnormal bleeding associated with sub optimal platelet function. We examined this concept and determined that killer whale platelets, in response to ADP, PAF, and arachidonic acid, appeared to aggregate normally during the first 2-5 minutes after addition of the agonist, but had completely disaggregated at 10 minutes. Collagen- and A23187-induced aggregation appeared normal and complete within 10 minutes, while there was no response to epinephrine or ristocetin. Thromboxane production by killer whale platelets appears to be quantitatively similar to that produced by human platelets in response to ADP and PAF and exceeded that produced by human platelets when collagen was used as the agonist. In summary, this study reports a reduced platelet aggregation reaction in killer whales in response to several platelet agonists which does not appear to be related to the generation of thromboxane. This phenomenon may serve a protective role in these mammals by preventing thrombosis during diving and resurfacing.

Adaptation, Physiological↗

Heavy metals in two populations of North Atlantic fin whales (Balaenoptera physalus).

Concentrations of cadmium, copper and zinc have been analyzed in muscle, liver and kidney tissues of fin whales (Balaenoptera physalus) from two locations in the North Atlantic, Iceland and Spain. The concentrations of zinc in the muscle and that of cadmium in the liver and the kidney were significantly higher in fin whales from Iceland. Other differences between whales from the two areas concern the dynamics of cadmium in the organism. These findings support the hypothesis that fin whales from the two sites belong to different stocks and that cadmium in the organism can be used as a complementary tool in studies of population identity.

Journal Article↗

Balaenoptera omurai is a newly discovered baleen whale that represents an ancient evolutionary lineage.

Balaenoptera omurai, formerly classified as a small form of Bryde's whale, was recently reclassified as a new baleen whale species of the family Balaenopteridae. Although researchers have investigated the evolutionary history of Balaenopteridae and their relatives using molecular phylogenetic methods, the taxonomy of the ordinary Bryde's whale (Balaenoptera brydei) and small-form Bryde's whales (Balaenoptera edeni and B. omurai) remains unclear. We have used complete mtDNA sequences and short interspersed repetitive element (SINE) insertion patterns to construct the evolutionary history of both B. omurai and the taxonomically redefined species, B. edeni. The combined results demonstrate that B. omurai forms a monophyletic lineage with B. musculus, B. brydei, B. edeni and B. borealis and that B. omurai and B. musculus successively diverged from their common ancestor. In addition, we also showed that B. edeni constitutes a sister taxon to B. brydei. Our data suggest that B. omurai evolved as an ancient independent lineage that diverged much earlier than B. borealis, B. brydei and B. edeni, which were previously believed to be closely related to B. omurai.

Animals↗

Mercury contamination in the red meat of whales and dolphins marketed for human consumption in Japan.

Cetacean products sold for human consumption in Japan originate from a wide range of whale, dolphin, and porpoise species caught off several areas of the Japan coast, Antarctic and North Pacific Oceans. We surveyed the total mercury (T-Hg) levels in red meat, the most popular cetacean products in Japan. We also analyzed the DNA of these to obtain information regarding species. According to the genetic analysis, the red meats originating from nine species of odontocete and six species of mystecete were sold in Japanese markets. T-Hg concentrations in all odontocete red meats (0.52-81.0 microg/wet g, n = 137) exceeded the provisional permitted level of T-Hg in marine foods set by the Japanese government (0.4 microg/wet g). The highest and second highest levels of T-Hg in the red meats were found in the false killer whale (81.0 microg/wet g) and striped dolphin (63.4 microg/wet g), respectively. These concentrations of T-Hg exceeded the permitted level of T-Hg by about 200 and 160 times, respectively, suggesting the possibility of chronic intoxication by methyl mercury due to frequent consumption of odontocete red meats. The T-Hg concentration levels were higher in odontocete species such as Baird's beaked whales and pilot whales caught off southern areas than those caught off northern areas, probably reflecting a higher Hg concentration in the seawater and/or their diet (squid and fish) in the southern area. On the other hand, T-Hg concentrations in all mystecete red meat samples except for one (0.01-0.54 microg/ wet g, n = 62) were below the permitted level of T-Hg, probably reflecting their lower trophic levels.

Animals↗

High-level expression of sperm whale myoglobin in Escherichia coli.

Sperm whale myoglobin was expressed in Escherichia coli from a totally synthetic gene inserted in the expression vector pUC19. The gene was constructed as 23 overlapping oligonucleotides encoding both strands of the DNA. Gene synthesis provides several advantages over traditional eukaryotic gene-cloning techniques, allowing the incorporation of an efficient ribosome binding site, appropriate initiation and termination sequences, restriction enzyme sites for convenient subcloning and future mutagenesis, and frequently used codons for highly expressed E. coli genes. The sperm whale myoglobin expressed from the synthetic gene constituted approximately 10% of the total soluble protein as holo-protein, indicating that iron-protoporphyrin IX biosynthesis and prosthetic-group incorporation are not limiting in the high-level expression of this heme protein in E. coli. We credit the use of frequently used E. coli codons for the observed high-level expression. The sperm whale myoglobin produced is stable, easily purified to homogeneity, and indistinguishable from commercially available sperm whale myoglobin by optical and magnetic spectroscopic methods.

Amino Acid Sequence↗

Sei whale sounds recorded in the Antarctic.

Sei whales are the least well known acoustically of all the rorquals, with only two brief descriptions of their calls previously reported. Recordings of low-frequency tonal and frequency swept calls were made near a group of four or five sei whales in waters west of the Antarctic Peninsula on 19 February 2003. These whales also produced broadband sounds which can be described as growls or whooshes. Many of the tonal and frequency swept calls (30 out of 68) consist of multiple parts with a frequency step between the two parts, this being the most unique characteristic of the calls, allowing them to be distinguished from the calls of other whale species. The average duration of the tonal calls is 0.45 +/- 0.3 s and the average frequency is 433 +/- 192 Hz. Using a calibrated seafloor recorder to determine the absolute calibration of a sonobuoy system, the maximum source level of the tonal calls was 156 +/- 3.6 dB re 1 microPa at 1 m. Each call had different character and there was no temporal pattern in the calling.

Acoustics↗

St. Lawrence blue whale vocalizations revisited: characterization of calls detected from 1998 to 2001.

From 1998 to 2001, 115 h of acoustic recordings were made in the presence of the well-studied St. Lawrence population of blue whales, using a calibrated omnidirectional hydrophone [flat (+/- 3 dB) response from 5 to 800 Hz] suspended at 50 m depth from a surface isolation buoy. The primary field site for this study was the estuary region of the St. Lawrence River (Québec, Canada), with most recordings made between mid-August and late October. During the recordings, detailed field notes were taken on all cetaceans within sight. Characterization of the more than 1000 blue whale calls detected during this study revealed that the St. Lawrence repertoire is much more extensive than previously reported. Three infrasonic (<20 Hz) and three audible range (30-200 Hz) call types were detected, with much time/frequency variation seen within each type. Further variation is seen in the form of call segmentation, which appears (through examination of Lloyd's Mirror interference effects) to be controlled at least partially by the whales. Although St. Lawrence blue whale call characteristics are similar to those of the North Atlantic, comparisons of phrase composition and spacing among studies suggest the possibility of population dialects within the North Atlantic.

Acoustics↗